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Cho H, Moy Y, Rudnick NA, Klein TM, Yin J, Bolar J, Hendrick C, Beatty M, Castañeda L, Kinney AJ, Jones TJ, Chilcoat ND. Development of an efficient marker-free soybean transformation method using the novel bacterium Ochrobactrum haywardense H1. PLANT BIOTECHNOLOGY JOURNAL 2022; 20:977-990. [PMID: 35015927 PMCID: PMC9055811 DOI: 10.1111/pbi.13777] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Revised: 12/15/2021] [Accepted: 12/28/2021] [Indexed: 05/03/2023]
Abstract
We have discovered a novel bacterium, Ochrobactrum haywardense H1 (Oh H1), which is capable of efficient plant transformation. Ochrobactrum is a new host for Agrobacterium-derived vir and T-DNA-mediated transformation. Oh H1 is a unique, non-phytopathogenic species, categorized as a BSL-1 organism. We engineered Oh H1 with repurposed Agrobacterium virulence machinery and demonstrated Oh H1 can transform numerous dicot species and at least one monocot, sorghum. We generated a cysteine auxotrophic Oh H1-8 strain containing a binary vector system. Oh H1-8 produced transgenic soybean plants with an efficiency 1.6 times that of Agrobacterium strain AGL1 and 2.9 times that of LBA4404Thy-. Oh H1-8 successfully transformed several elite Corteva soybean varieties with T0 transformation frequency up to 35%. In addition to higher transformation efficiencies, Oh H1-8 generated high-quality, transgenic events with single-copy, plasmid backbone-free insertion at frequencies higher than AGL1. The SpcN selectable marker gene is excised using a heat shock-inducible excision system resulting in marker-free transgenic events. Approximately, 24.5% of the regenerated plants contained only a single copy of the transgene and contained no vector backbone. There were no statistically significant differences in yield comparing T3 null-segregant lines to wild-type controls. We have demonstrated that Oh H1-8, combined with spectinomycin selection, is an efficient, rapid, marker-free and yield-neutral transformation system for elite soybean.
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Affiliation(s)
- Hyeon‐Je Cho
- Research and DevelopmentCorteva AgriscienceJohnstonIAUSA
| | - York Moy
- Research and DevelopmentCorteva AgriscienceJohnstonIAUSA
- Alpine Roads Inc.South San FranciscoCAUSA
| | - Nathan A. Rudnick
- Research and DevelopmentCorteva AgriscienceJohnstonIAUSA
- Relic Culture LLC.San LeandroCAUSA
| | - Theodore M. Klein
- Research and DevelopmentCorteva AgriscienceJohnstonIAUSA
- Meristematic Inc.San FranciscoCAUSA
| | - Jiaming Yin
- Research and DevelopmentCorteva AgriscienceJohnstonIAUSA
| | - Joy Bolar
- Research and DevelopmentCorteva AgriscienceJohnstonIAUSA
| | - Carol Hendrick
- Research and DevelopmentCorteva AgriscienceJohnstonIAUSA
| | - Mary Beatty
- Research and DevelopmentCorteva AgriscienceJohnstonIAUSA
| | | | | | - Todd J. Jones
- Research and DevelopmentCorteva AgriscienceJohnstonIAUSA
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Dormatey R, Sun C, Ali K, Fiaz S, Xu D, Calderón-Urrea A, Bi Z, Zhang J, Bai J. ptxD/Phi as alternative selectable marker system for genetic transformation for bio-safety concerns: a review. PeerJ 2021; 9:e11809. [PMID: 34395075 PMCID: PMC8323600 DOI: 10.7717/peerj.11809] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Accepted: 06/27/2021] [Indexed: 12/14/2022] Open
Abstract
Antibiotic and herbicide resistance genes are the most common marker genes for plant transformation to improve crop yield and food quality. However, there is public concern about the use of resistance marker genes in food crops due to the risk of potential gene flow from transgenic plants to compatible weedy relatives, leading to the possible development of “superweeds” and antibiotic resistance. Several selectable marker genes such as aph, nptII, aaC3, aadA, pat, bar, epsp and gat, which have been synthesized to generate transgenic plants by genetic transformation, have shown some limitations. These marker genes, which confer antibiotic or herbicide resistance and are introduced into crops along with economically valuable genes, have three main problems: selective agents have negative effects on plant cell proliferation and differentiation, uncertainty about the environmental effects of many selectable marker genes, and difficulty in performing recurrent transformations with the same selectable marker to pyramid desired genes. Recently, a simple, novel, and affordable method was presented for plant cells to convert non-metabolizable phosphite (Phi) to an important phosphate (Pi) for developing cells by gene expression encoding a phosphite oxidoreductase (PTXD) enzyme. The ptxD gene, in combination with a selection medium containing Phi as the sole phosphorus (P) source, can serve as an effective and efficient system for selecting transformed cells. The selection system adds nutrients to transgenic plants without potential risks to the environment. The ptxD/Phi system has been shown to be a promising transgenic selection system with several advantages in cost and safety compared to other antibiotic-based selection systems. In this review, we have summarized the development of selection markers for genetic transformation and the potential use of the ptxD/Phi scheme as an alternative selection marker system to minimize the future use of antibiotic and herbicide marker genes.
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Affiliation(s)
- Richard Dormatey
- Gansu Provincial Key Laboratory of Aridland Crop Science/College of Agronomy, Gansu Agricultural University, Landzhou, China
| | - Chao Sun
- Gansu Provincial Key Laboratory of Aridland Crop Science/College of Agronomy, Gansu Agricultural University, Landzhou, China
| | - Kazim Ali
- Gansu Provincial Key Laboratory of Aridland Crop Science/College of Agronomy, Gansu Agricultural University, Landzhou, China.,National Institute for Genomics and Advanced Biotechnology, National Agricultural Research Centre, Park Road, Islamabad Pakistan
| | - Sajid Fiaz
- Department of Plant Breeding and Genetics, The University of Haripur, Haripur, Pakistan
| | - Derong Xu
- Gansu Provincial Key Laboratory of Aridland Crop Science/College of Agronomy, Gansu Agricultural University, Landzhou, China
| | - Alejandro Calderón-Urrea
- Department of Biology, College of Science and Mathematics, California State University, Fresno, CA, USA
| | - Zhenzhen Bi
- Gansu Provincial Key Laboratory of Aridland Crop Science/College of Agronomy, Gansu Agricultural University, Landzhou, China
| | - Junlian Zhang
- Gansu Provincial Key Laboratory of Aridland Crop Science/College of Agronomy, Gansu Agricultural University, Landzhou, China
| | - Jiangping Bai
- Gansu Provincial Key Laboratory of Aridland Crop Science/College of Agronomy, Gansu Agricultural University, Landzhou, China
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Klenov A, Hudak KA. Facile method of curing toxicity in large viral genomes by high-throughput identification and removal of cryptic promoters. J Virol Methods 2020; 287:113993. [PMID: 33068704 DOI: 10.1016/j.jviromet.2020.113993] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 10/05/2020] [Accepted: 10/08/2020] [Indexed: 01/09/2023]
Abstract
Infectious plant virus clones are challenging to construct and manipulate due to the presence of cryptic promoter sequences that induce toxicity in bacteria. Common methods to overcome toxicity include intron insertion to interrupt toxic open reading frames and the use of Rhizobium or yeast species that do not recognize the same cryptic promoters. Unfortunately, intron insertion must be attempted on a trial and error basis within full-length clones and may change the infection characteristics of the virus. We have developed a facile method that can detect multiple cryptic bacterial promoters within large virus genomes. These promoters can then be silenced to obtain infectious clones that can be manipulated in E. coli. Our strategy relies on the generation of a viral library which is cloned upstream of either an eGFP open reading frame for low-throughput analysis or chloramphenicol for next generation sequencing. Pokeweed mosaic virus (PkMV), a 9.5 Kb ssRNA potyvirus, was used as a proof of concept. We found 16 putative promoter regions within 150-250 bp library fragments throughout the PkMV genome. 5'RACE allowed identification of the promoter sequence within each fragment, and subsequent silencing produced infectious clones. Our results indicate that cryptic promoters are ubiquitous within large viral genomes and that promoter screening is a desirable first step when constructing a viral clone. Our method can be applied to large plant and animal viruses as well as any DNA sequence for which low level of background transcriptional activity is required.
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Liu F, Wang P, Xiong X, Fu P, Gao H, Ding X, Wu G. Comparison of three Agrobacterium-mediated co-transformation methods for generating marker-free transgenic Brassica napus plants. PLANT METHODS 2020; 16:81. [PMID: 32518583 PMCID: PMC7275470 DOI: 10.1186/s13007-020-00628-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Accepted: 06/01/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND Generation of marker-free transgenic plants is very important to the regulatory permission and commercial release of transgenic crops. Co-transformation methods that enable the removal of selectable marker genes have been extensively used because they are simple and clean. Few comparisons are currently available between different strain/plasmid co-transformation systems, and also data are related to variation in co-transformation frequencies caused by other details of the vector design. RESULTS In this study, we constructed three vector systems for the co-transformation of allotetraploid Brassica napus (B. napus) mediated by Agrobacterium tumefaciens and compared these co-transformation methods. We tested a mixed-strain system, in which a single T-DNA is harbored in two plasmids, as well as two "double T-DNA" vector systems, in which two independent T-DNAs are harbored in one plasmid in a tandem orientation or in an inverted orientation. As confirmed by the use of PCR analysis, test strips, and Southern blot, the average co-transformation frequencies from these systems ranged from 24 to 81% in T0 plants, with the highest frequency of 81% for 1:1 treatment of the mixed-strain system. These vector systems are valuable for generating marker-free transgenic B. napus plants, and marker-free plants were successfully obtained in the T1 generation from 50 to 77% of T0 transgenic lines using these systems, with the highest frequency of 77% for "double T-DNA" vector systems of pBID RT Enhanced. We further found that marker-free B. napus plants were more frequently encountered in the progeny of transgenic lines which has only one or two marker gene copies in the T0 generation. Two types of herbicide resistant transgenic B. napus plants, Bar + with phosphinothricin resistance and Bar + EPSPS + GOX + with phosphinothricin and glyphosate resistance, were obtained. CONCLUSION We were successful in removing selectable marker genes in transgenic B. napus plants using all three co-transformation systems developed in this study. It was proved that if a appropriate mole ratio was designed for the specific length ratio of the twin T-DNAs for the mixed-strain method, high unlinked co-insertion frequency and overall success frequency could be achieved. Our study provides useful information for the construction of efficient co-transformation system for marker-free transgenic crop production and developed transgenic B. napus with various types of herbicide resistance.
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Affiliation(s)
- Fang Liu
- Key Laboratory of Biology and Genetics Improvement of Oil Crops, Ministry of Agriculture and Rural Affairs, Oil Crops Research Institute, Chinese Academy of Agricultural Sciences, Wuhan, China
| | - Pandi Wang
- Key Laboratory of Biology and Genetics Improvement of Oil Crops, Ministry of Agriculture and Rural Affairs, Oil Crops Research Institute, Chinese Academy of Agricultural Sciences, Wuhan, China
| | - Xiaojuan Xiong
- Key Laboratory of Biology and Genetics Improvement of Oil Crops, Ministry of Agriculture and Rural Affairs, Oil Crops Research Institute, Chinese Academy of Agricultural Sciences, Wuhan, China
| | - Ping Fu
- Key Laboratory of Biology and Genetics Improvement of Oil Crops, Ministry of Agriculture and Rural Affairs, Oil Crops Research Institute, Chinese Academy of Agricultural Sciences, Wuhan, China
| | - Hongfei Gao
- Key Laboratory of Biology and Genetics Improvement of Oil Crops, Ministry of Agriculture and Rural Affairs, Oil Crops Research Institute, Chinese Academy of Agricultural Sciences, Wuhan, China
| | - Xinhua Ding
- State Key Laboratory of Crop Biology, College of Plant Protection, Shandong Agricultural University, Tai’an, 271018 Shandong China
| | - Gang Wu
- Key Laboratory of Biology and Genetics Improvement of Oil Crops, Ministry of Agriculture and Rural Affairs, Oil Crops Research Institute, Chinese Academy of Agricultural Sciences, Wuhan, China
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Agrobacterium-mediated horizontal gene transfer: Mechanism, biotechnological application, potential risk and forestalling strategy. Biotechnol Adv 2018; 37:259-270. [PMID: 30579929 DOI: 10.1016/j.biotechadv.2018.12.008] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2018] [Revised: 12/18/2018] [Accepted: 12/18/2018] [Indexed: 11/20/2022]
Abstract
The extraordinary capacity of Agrobacterium to transfer its genetic material to host cell makes it evolve from phytopathogen to a powerful transgenic vector. Agrobacterium-mediated stable transformation is widely used as the preferred method to create transgenic plants for molecular plant biology research and crop breeding. Recent years, both mechanism and application of Agrobacterium-mediated horizontal gene transfer have made significant progresses, especially Agrobacterium-mediated transient transformation was developed for plant biotechnology industry to produce recombinant proteins. Agrobacterium strains are almost used and saved not only by each of microbiology and molecular plant labs, but also by many of plant biotechnology manufacturers. Agrobacterium is able to transfer its genetic material to a broad range of hosts, including plant and non-plant hosts. As a consequence, the concern of environmental risk associated with the accidental release of genetically modified Agrobacterium arises. In this article, we outline the recent progress in the molecular mechanism of Agrobacterium-meditated gene transfer, focus on the application of Agrobacterium-mediated horizontal gene transfer, and review the potential risk associated with Agrobacterium-meditated gene transfer. Based on the comparison between the infecting process of Agrobacterium as a pathogen and the transgenic process of Agrobacterium as a transgenic vector, we realize that chemotaxis is the distinct difference between these two biological processes and thus discuss the possible role of chemotaxis in forestalling the potential risk of Agrobacterium-meditated horizontal gene transfer to non-target plant species.
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Yaqoob U, Kaul T, Nawchoo IA. Development of an efficient protocol for Agrobacterium mediated transformation of some recalcitrant indica rice varieties. ACTA ACUST UNITED AC 2017. [DOI: 10.1007/s40502-017-0304-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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7
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Feng D, Wang Y, Wu J, Lu T, Zhang Z. Development and drought tolerance assay of marker-free transgenic rice with OsAPX2 using biolistic particle-mediated co-transformation. ACTA ACUST UNITED AC 2017. [DOI: 10.1016/j.cj.2017.04.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Guo WC, Wang ZA, Luo XL, Jin X, Chang J, He J, Tu EX, Tian YC, Si HJ, Wu JH. Development of selectable marker-free transgenic potato plants expressing cry3A against the Colorado potato beetle (Leptinotarsa decemlineata Say). PEST MANAGEMENT SCIENCE 2016; 72:497-504. [PMID: 25820984 DOI: 10.1002/ps.4013] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Revised: 03/11/2015] [Accepted: 03/23/2015] [Indexed: 06/04/2023]
Abstract
BACKGROUND Elimination of selectable marker genes (SMGs) is important for the safe assessment and commercial use of transgenic plants. The destructive and invasive Colorado potato beetle (CPB) poses a serious threat to potato production. In response to this need, selectable marker-free transgenic potato lines expressing cry3A were developed to control the damage and spread of CPB. RESULTS We simultaneously introduced cry3A and npt II genes harboured in different plasmids into the potato genome using the Agrobacterium-mediated cotransformation method. Four selectable marker-free transgenic potato (CT) lines expressing cry3A were developed by self-crossing segregation and molecular analyses, including Southern blot, western blot and enzyme-linked immunosorbent assay (ELISA) assays. CT lines were used in a resistance bioassay against CPB in the laboratory and field. In the laboratory, CT lines exhibited high resistance to CPB, and 100% mortality of first-instar larvae occurred 6 days after infestation. In the field, untransformed plant leaves were almost entirely consumed, with an average of 155 larvae present per plant 25 days after inoculation. However, CT lines showed no damage symptoms, with approximately 2.5 larvae surviving per plant. CONCLUSION We successfully eliminated SMGs from the transgenic potato lines expressing cry3A in order to decrease CPB damage, control the spread of this pest eastwards and alleviate the concern regarding the safe assessment of regulatory requirements. © 2015 Society of Chemical Industry.
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Affiliation(s)
- Wen-chao Guo
- State Key Laboratory of Plant Genome, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
- Institute of Plant Protection, Xinjiang Agricultural Academy of Sciences, Xinjiang, Urumqi, China
| | - Zhi-an Wang
- State Key Laboratory of Plant Genome, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
- Institute of Cotton Research, Shanxi Agricultural Academy of Sciences, Shanxi, Yuncheng, China
| | - Xiao-li Luo
- Institute of Cotton Research, Shanxi Agricultural Academy of Sciences, Shanxi, Yuncheng, China
| | - Xin Jin
- State Key Laboratory of Plant Genome, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
- College of Biology Science and Technology, Gansu Agricultural University, Gansu, Lanzhou, China
| | - Jing Chang
- State Key Laboratory of Plant Genome, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
- College of Biology Science and Technology, Gansu Agricultural University, Gansu, Lanzhou, China
| | - Jiang He
- Institute of Plant Protection, Xinjiang Agricultural Academy of Sciences, Xinjiang, Urumqi, China
| | - Er-xun Tu
- Institute of Plant Protection, Xinjiang Agricultural Academy of Sciences, Xinjiang, Urumqi, China
| | - Ying-chuan Tian
- State Key Laboratory of Plant Genome, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Huai-jun Si
- College of Biology Science and Technology, Gansu Agricultural University, Gansu, Lanzhou, China
| | - Jia-he Wu
- State Key Laboratory of Plant Genome, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
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Birla DS, Malik K, Sainger M, Chaudhary D, Jaiwal R, Jaiwal PK. Progress and challenges in improving the nutritional quality of rice (Oryza sativaL.). Crit Rev Food Sci Nutr 2015; 57:2455-2481. [DOI: 10.1080/10408398.2015.1084992] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Deep Shikha Birla
- Centre for Biotechnology, Maharshi Dayanand University, Rohtak, India
| | - Kapil Malik
- Centre for Biotechnology, Maharshi Dayanand University, Rohtak, India
| | - Manish Sainger
- Centre for Biotechnology, Maharshi Dayanand University, Rohtak, India
| | - Darshna Chaudhary
- Centre for Biotechnology, Maharshi Dayanand University, Rohtak, India
| | - Ranjana Jaiwal
- Department of Zoology, Maharshi Dayanand University, Rohtak, India
| | - Pawan K. Jaiwal
- Centre for Biotechnology, Maharshi Dayanand University, Rohtak, India
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Takaiwa F, Wakasa Y, Takagi H, Hiroi T. Rice seed for delivery of vaccines to gut mucosal immune tissues. PLANT BIOTECHNOLOGY JOURNAL 2015; 13:1041-55. [PMID: 26100952 DOI: 10.1111/pbi.12423] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Revised: 05/14/2015] [Accepted: 05/23/2015] [Indexed: 05/09/2023]
Abstract
Gut-associated lymphoid tissue (GALT) is the biggest lymphoid organ in the body. It plays a role in robust immune responses against invading pathogens while maintaining immune tolerance against nonpathogenic antigens such as foods. Oral vaccination can induce mucosal and systemic antigen-specific immune reactions and has several advantages including ease of administration, no requirement for purification and ease of scale-up of antigen. Thus far, taking advantage of these properties, various plant-based oral vaccines have been developed. Seeds provide a superior production platform over other plant tissues for oral vaccines; they offer a suitable delivery vehicle to GALT due to their high stability at room temperature, ample and stable deposition space, high expression level, and protection from digestive enzymes in gut. A rice seed production system for oral vaccines was established by combining stable deposition in protein bodies or protein storage vacuoles and enhanced endosperm-specific expression. Various types of rice-based oral vaccines for infectious and allergic diseases were generated. Efficacy of these rice-based vaccines was evaluated in animal models.
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Affiliation(s)
- Fumio Takaiwa
- Functional Crop Research and Development Unit, National Institute of Agrobiological Sciences, Tsukuba, Ibaraki, Japan
| | - Yuhya Wakasa
- Functional Crop Research and Development Unit, National Institute of Agrobiological Sciences, Tsukuba, Ibaraki, Japan
| | - Hidenori Takagi
- Functional Crop Research and Development Unit, National Institute of Agrobiological Sciences, Tsukuba, Ibaraki, Japan
| | - Takachika Hiroi
- Department of Allergy and Immunology, The Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
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Zhi L, TeRonde S, Meyer S, Arling ML, Register JC, Zhao ZY, Jones TJ, Anand A. Effect of Agrobacterium strain and plasmid copy number on transformation frequency, event quality and usable event quality in an elite maize cultivar. PLANT CELL REPORTS 2015; 34:745-54. [PMID: 25558819 DOI: 10.1007/s00299-014-1734-0] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2014] [Revised: 12/17/2014] [Accepted: 12/19/2014] [Indexed: 05/26/2023]
Abstract
Improving Agrobacterium -mediated transformation frequency and event quality by increasing binary plasmid copy number and appropriate strain selection is reported in an elite maize cultivar. Agrobacterium-mediated maize transformation is a well-established method for gene testing and for introducing useful traits in a commercial biotech product pipeline. To develop a highly efficient maize transformation system, we investigated the effect of two Agrobacterium tumefaciens strains and three different binary plasmid origins of replication (ORI) on transformation frequency, vector backbone insertion, single copy event frequency (percentage of events which are single copy for all transgenes), quality event frequency (percentage of single copy events with no vector backbone insertions among all events generated; QE) and usable event quality frequency (transformation frequency times QE frequency; UE) in an elite maize cultivar PHR03. Agrobacterium strain AGL0 gave a higher transformation frequency, but a reduced QE frequency than LBA4404 due to a higher number of vector backbone insertions. Higher binary plasmid copy number positively correlated with transformation frequency and usable event recovery. The above findings can be exploited to develop high-throughput transformation protocols, improve the quality of transgenic events in maize and other plants.
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Affiliation(s)
- Li Zhi
- DuPont Agricultural Biotechnology, DuPont-Pioneer, 8305 NW 62nd Avenue, P. O. Box 7060, Johnston, IA, 50131, USA
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Anil Kumar S, Hima Kumari P, Shravan Kumar G, Mohanalatha C, Kavi Kishor PB. Osmotin: a plant sentinel and a possible agonist of mammalian adiponectin. FRONTIERS IN PLANT SCIENCE 2015; 6:163. [PMID: 25852715 PMCID: PMC4360817 DOI: 10.3389/fpls.2015.00163] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2014] [Accepted: 03/01/2015] [Indexed: 05/18/2023]
Abstract
Osmotin is a stress responsive antifungal protein belonging to the pathogenesis-related (PR)-5 family that confers tolerance to both biotic and abiotic stresses in plants. Protective efforts of osmotin in plants range from high temperature to cold and salt to drought. It lyses the plasma membrane of the pathogens. It is widely distributed in fruits and vegetables. It is a differentially expressed and developmentally regulated protein that protects the cells from osmotic stress and invading pathogens as well, by structural or metabolic alterations. During stress conditions, osmotin helps in the accumulation of the osmolyte proline, which quenches reactive oxygen species and free radicals. Osmotin expression results in the accumulation of storage reserves and increases the shelf-life of fruits. It binds to a seven-transmembrane-domain receptor-like protein and induces programmed cell death in Saccharomyces cerevisiae through RAS2/cAMP signaling pathway. Adiponectin, produced in adipose tissues of mammals, is an insulin-sensitizing hormone. Strangely, osmotin acts like the mammalian hormone adiponectin in various in vitro and in vivo models. Adiponectin and osmotin, the two receptor binding proteins do not share sequence similarity at the amino acid level, but interestingly they have a similar structural and functional properties. In experimental mice, adiponectin inhibits endothelial cell proliferation and migration, primary tumor growth, and reduces atherosclerosis. This retrospective work examines the vital role of osmotin in plant defense and as a potential targeted therapeutic drug for humans.
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Affiliation(s)
- S. Anil Kumar
- Department of Genetics, Osmania University, HyderabadIndia
| | - P. Hima Kumari
- Department of Genetics, Osmania University, HyderabadIndia
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Ramkumar TR, Parameswari C, Sugapriya T, Veluthambi K. Effect of orientation of transcription of a gene in an inverted transferred DNA repeat on transcriptional gene silencing in rice transgenics-a case study. PHYSIOLOGY AND MOLECULAR BIOLOGY OF PLANTS : AN INTERNATIONAL JOURNAL OF FUNCTIONAL PLANT BIOLOGY 2015; 21:151-157. [PMID: 25648206 PMCID: PMC4312324 DOI: 10.1007/s12298-014-0273-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2014] [Revised: 12/03/2014] [Accepted: 12/04/2014] [Indexed: 06/04/2023]
Abstract
We studied transgene silencing in two transgenic rice plants, OSM25 and COT-OSM4, which harboured two different types of right border (RB)-centered inverted transferred DNA (T-DNA) repeats (IRs). The T-DNA in OSM25 has three genes gus, OSM and hph, all under the transcriptional control of the Cauliflower mosaic virus 35S promoter (P35S). The gus gene, which is proximal to the RB, is in a convergent orientation of transcription in the IR. OSM25 displayed silencing of all three transgenes. Nuclear run-on transcription analysis revealed that silencing of gus, OSM and hph genes in OSM25 operates at the transcriptional level. P35S showed hypermethylation in OSM25 plants. COT-OSM4 has P35S-driven gus and hph genes in its T-DNA. The hph gene, which is proximal to the RB, is in a divergent orientation of transcription in the IR. Unlike in OSM25, the transgenes in COT-OSM4 showed no silencing. These findings show that convergent orientation of transcription of a gene at the origin of an IR is important for transgene silencing.
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Affiliation(s)
- Thakku R. Ramkumar
- Department of Plant Biotechnology, School of Biotechnology, Madurai Kamaraj University, Madurai, 625021 Tamil Nadu India
| | - Chidambaram Parameswari
- Department of Plant Biotechnology, School of Biotechnology, Madurai Kamaraj University, Madurai, 625021 Tamil Nadu India
| | - Thennavan Sugapriya
- Department of Plant Biotechnology, School of Biotechnology, Madurai Kamaraj University, Madurai, 625021 Tamil Nadu India
| | - Karuppannan Veluthambi
- Department of Plant Biotechnology, School of Biotechnology, Madurai Kamaraj University, Madurai, 625021 Tamil Nadu India
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Matheka JM, Anami S, Gethi J, Omer RA, Alakonya A, Machuka J, Runo S. A new double right border binary vector for producing marker-free transgenic plants. BMC Res Notes 2013; 6:448. [PMID: 24207020 PMCID: PMC3829385 DOI: 10.1186/1756-0500-6-448] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2013] [Accepted: 11/05/2013] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND Once a transgenic plant is developed, the selectable marker gene (SMG) becomes unnecessary in the plant. In fact, the continued presence of the SMG in the transgenic plant may cause unexpected pleiotropic effects as well as environmental or biosafety issues. Several methods for removal of SMGs that have been reported remain inaccessible due to protection by patents, while development of new ones is expensive and cost prohibitive. Here, we describe the development of a new vector for producing marker-free plants by simply adapting an ordinary binary vector to the double right border (DRB) vector design using conventional cloning procedures. FINDINGS We developed the DRB vector pMarkfree5.0 by placing the bar gene (representing genes of interest) between two copies of T-DNA right border sequences. The β-glucuronidase (gus) and nptII genes (representing the selectable marker gene) were cloned next followed by one copy of the left border sequence. When tested in a model species (tobacco), this vector system enabled the generation of 55.6% kanamycin-resistant plants by Agrobacterium-mediated transformation. The frequency of cotransformation of the nptII and bar transgenes using the vector was 66.7%. Using the leaf bleach and Basta assays, we confirmed that the nptII and bar transgenes were coexpressed and segregated independently in the transgenic plants. This enable separation of the transgenes in plants cotransformed using pMarkfree5.0. CONCLUSIONS The results suggest that the DRB system developed here is a practical and effective approach for separation of gene(s) of interest from a SMG and production of SMG-free plants. Therefore this system could be instrumental in production of "clean" plants containing genes of agronomic importance.
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Affiliation(s)
- Jonathan M Matheka
- Biochemistry and Biotechnology Department, Kenyatta University, P. O. Box 43844, 00100 Nairobi, Kenya
| | - Sylvester Anami
- Institute for Biotechnology Research, Jomo Kenyatta University of Agriculture and Technology, P.O. Box 62000–00100, Nairobi, Kenya
| | - James Gethi
- Kenya Agricultural Research Institute, P.O. Box 340–90100, Machakos, Kenya
| | - Rasha A Omer
- Biosafety and Biotechnology Research Center, Agricultural Research Corporation, P.O. Box 126, Wad Medani, Sudan
| | - Amos Alakonya
- Institute for Biotechnology Research, Jomo Kenyatta University of Agriculture and Technology, P.O. Box 62000–00100, Nairobi, Kenya
| | - Jesse Machuka
- Biochemistry and Biotechnology Department, Kenyatta University, P. O. Box 43844, 00100 Nairobi, Kenya
| | - Steven Runo
- Biochemistry and Biotechnology Department, Kenyatta University, P. O. Box 43844, 00100 Nairobi, Kenya
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Bala A, Roy A, Das A, Chakraborti D, Das S. Development of selectable marker free, insect resistant, transgenic mustard (Brassica juncea) plants using Cre/lox mediated recombination. BMC Biotechnol 2013; 13:88. [PMID: 24144281 PMCID: PMC3819271 DOI: 10.1186/1472-6750-13-88] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2013] [Accepted: 10/08/2013] [Indexed: 01/12/2023] Open
Abstract
Background Antibiotic/ herbicide resistant marker genes have been proven to be very useful in plant transformation for the initial selection of desired transgenic events. However, presence of these genes in the genetically modified crops may render the crop less acceptable to the consumers. Among several different approaches, the effectiveness of Cre/lox mediated recombination strategy for selectable marker gene (SMG) elimination has previously been demonstrated by different groups in several plants including Brassica. In the present study exploiting Cre/lox mediated recombination strategy, attempt has been made for selectable marker gene elimination from Allium sativum leaf agglutinin (ASAL) expressing Brassica plants with hemipteran insect resistant phenotype. Results Allium sativum leaf agglutinin (ASAL) linked with lox flanked hygromycin resistant (hpt) gene was introduced in mustard. Cre recombinase gene cassette was also integrated in separate event. A Cre/lox mediated recombination using crossing strategy was adopted to remove the hpt gene from the subsequent generation of selected hybrid events. Reciprocal crosses were made between T1ASAL-lox-hpt-lox and cre-bar plants. Marker gene elimination was confirmed in the resulting F1 hybrid progenies by PCR analysis, using hpt, cre and ASAL specific primers followed by Southern hybridization. In marker free plants, expression of ASAL was also confirmed by western blotting and ELISA analysis. Retention of functionality of expressed ASAL was investigated by agglutination assay using rabbit erythrocytes. Expressed ASAL was also found to be thermo-sensitive. In planta insect bioassay on F1 hybrid progenies exhibited detrimental effect on the performance of devastating target pest, Lipaphis erysimi. The F1 hybrid hpt negative, ASAL positive plants were allowed to self- fertilize to obtain F2 progeny plants. In some of these plants cre gene was found to be segregated out of the ASAL gene by genetic segregation yielding completely marker free plants. Conclusions The present study establishes the efficient expression of the newly introduced insect resistant ASAL gene even after Cre/lox mediated recombination resulting in elimination of selectable marker gene.
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Affiliation(s)
| | | | | | | | - Sampa Das
- Division of Plant Biology, Bose Institute, P1/12, C, I, T Scheme VIIM, Kolkata 700054, WB, India.
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Wakasa Y, Takaiwa F. The use of rice seeds to produce human pharmaceuticals for oral therapy. Biotechnol J 2013; 8:1133-43. [PMID: 24092672 DOI: 10.1002/biot.201300065] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2013] [Revised: 07/14/2013] [Accepted: 08/23/2013] [Indexed: 11/09/2022]
Abstract
Rice (Oryza sativa L.) is the major staple food consumed by half of the world's population. Rice seeds have gained recent attention as bioreactors for the production of human pharmaceuticals such as therapeutic proteins or peptides. Rice seed production platforms have many advantages over animal cell or microbe systems in terms of cost-effectiveness, scalability, safety, product stability and productivity. Rice seed-based human pharmaceuticals are expected to become innovative therapies as edible drugs. Therapeutic proteins can be sequestered within natural cellular compartments in rice seeds and protected from harsh gastrointestinal environments. This review presents the state-of-the-art on the construction of gene cassettes for accumulation of pharmaceutical proteins or peptides in rice seeds, the generation of transgenic rice plants, and challenges involved in the use of rice seeds to produce human pharmaceuticals.
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Affiliation(s)
- Yuhya Wakasa
- Functional Transgenic Crops Research Unit, Genetically Modified Organism Research Center, National Institute of Agrobiological Sciences, Ibaraki, Japan
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Wakasa Y, Ozawa K, Takaiwa F. Agrobacterium-mediated co-transformation of rice using two selectable marker genes derived from rice genome components. PLANT CELL REPORTS 2012; 31:2075-2084. [PMID: 22843026 DOI: 10.1007/s00299-012-1318-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2012] [Revised: 07/01/2012] [Accepted: 07/13/2012] [Indexed: 06/01/2023]
Abstract
A method for Agrobacterium-mediated co-transformation of rice (Oryza sativa L.) was developed using rice-derived selection markers. Two T-DNAs were efficiently introduced into separate loci using selectable marker gene cassettes consisting of the mutated acetolactate synthase gene (mALS) under the control of the callus-specific promoter (CSP) (CSP:mALS) and the ferredoxin nitrite reductase gene (NiR) under the control of its own promoter (NiR P:NiR). The CSP:mALS gene cassette confers sulfonylurea herbicide resistance to transgenic rice callus. The NiR P:NiR construct complements NiR-deficient mutant cultivars such as 'Koshihikari', which are defective in the regulation of nitrogen metabolism. In the present study, the CaMV35S:GUS and CaMV35S:GFP gene cassettes were co-introduced into the 'Koshihikari' genome using our system. Approximately 5-10 independent transgenic lines expressing both the GUS and GFP reporters were obtained from 100 Agrobacterium co-inoculated calli. Furthermore, transgenic 'Koshihikari' rice lines with reduced content of two major seed allergen proteins, the 33 and 14-16 kDa allergens, were generated by this co-transformation system. The present results indicate that the generation of selectable antibiotic resistance marker gene-free transgenic rice is possible using our rice-derived selection marker co-transformation system. Key message An improved rice transformation method was developed based on Agrobacterium-mediated co-transformation using two rice genome-derived selectable marker gene cassettes.
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Affiliation(s)
- Yuhya Wakasa
- Functional Transgenic Crops Research Unit, Genetically Modified Organism Research Center, National Institute of Agrobiological Sciences, Kannondai 2-1-2, Tsukuba, Ibaraki, 305-8602, Japan.
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Mehrotra S, Goyal V. Agrobacterium-mediated gene transfer in plants and biosafety considerations. Appl Biochem Biotechnol 2012; 168:1953-75. [PMID: 23090683 DOI: 10.1007/s12010-012-9910-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2012] [Accepted: 10/03/2012] [Indexed: 12/21/2022]
Abstract
Agrobacterium, the natures' genetic engineer, has been used as a vector to create transgenic plants. Agrobacterium-mediated gene transfer in plants is a highly efficient transformation process which is governed by various factors including genotype of the host plant, explant, vector, plasmid, bacterial strain, composition of culture medium, tissue damage, and temperature of co-cultivation. Agrobacterium has been successfully used to transform various economically and horticulturally important monocot and dicot species by standard tissue culture and in planta transformation techniques like floral or seedling infilteration, apical meristem transformation, and the pistil drip methods. Monocots have been comparatively difficult to transform by Agrobacterium. However, successful transformations have been reported in the last few years based on the adjustment of the parameters that govern the responses of monocots to Agrobacterium. A novel Agrobacterium transferred DNA-derived nanocomplex method has been developed which will be highly valuable for plant biology and biotechnology. Agrobacterium-mediated genetic transformation is known to be the preferred method of creating transgenic plants from a commercial and biosafety perspective. Agrobacterium-mediated gene transfer predominantly results in the integration of foreign genes at a single locus in the host plant, without associated vector backbone and is also known to produce marker free plants, which are the prerequisites for commercialization of transgenic crops. Research in Agrobacterium-mediated transformation can provide new and novel insights into the understanding of the regulatory process controlling molecular, cellular, biochemical, physiological, and developmental processes occurring during Agrobacterium-mediated transformation and also into a wide range of aspects on biological safety of transgenic crops to improve crop production to meet the demands of ever-growing world's population.
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Affiliation(s)
- Shweta Mehrotra
- National Research Centre on Plant Biotechnology, Lal Bahadur Shastri Building, Pusa Campus, New Delhi 110012, India.
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Tuteja N, Verma S, Sahoo RK, Raveendar S, Reddy INBL. Recent advances in development of marker-free transgenic plants: Regulation and biosafety concern. J Biosci 2012; 37:167-97. [PMID: 22357214 DOI: 10.1007/s12038-012-9187-5] [Citation(s) in RCA: 103] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Affiliation(s)
- Narendra Tuteja
- International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi 110 067, India.
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